Here are some examples of lip syncing gone wrong. We have a singer with an upside down microphone, a singer who falls off stage and keeps singing flawlessly and a singer who drops his mic and yet his vocal levels remain perfect. Why did I post these? Because they are funny.
“In the case of live concert performances, lip-synching is a commonly-used shortcut, but it can be considered controversial.” – Wikipedia
For more info: Music’s 15 Most Notorious Fakers & Lip-Synchers